1. Field of the Invention
This invention relates generally to rifle triggers, and specifically to double set triggers where the rear trigger serves to reduce the pull force on the forward firing trigger.
2. Description of the Prior Art
Sportsmen who engage in competitive bench rest shooting generally use special competition triggers to enhance accuracy. Important features of a competition trigger are light pull force, short lock time, and low vibration. Light pull force, usually approximately two ounces, decreases movement of the rifle in response to the pull of the trigger. Short lock time decreases movement of the rifle by decreasing the interval after the trigger is pulled and prior to ignition of the cartridge. Low vibration decreases movement of the rifle in response to the movement of the trigger mechanism.
The light pull force of a competition trigger is attained by a combination of low spring force on the trigger and reduction of friction on the trigger catch. In a standard trigger, the trigger catch restrains a sear which in turn restrains the firing pin. Competition triggers generally have a middle lever between the sear and the trigger that provides a mechanical advantage to reduce the force on the trigger catch.
Competition triggers are not generally used in hunting rifles because they are liable to accidental discharge. The light spring force that restrains the trigger in its cocked position is easily overcome by the impacts frequently encountered during hunting. Hunting rifles generally have a much higher pull force, usually approximately three pounds, to prevent accidental discharge resulting from impact.
The prior art of double set triggers, for example Repa, in U.S. Pat. No. 4,499,684, combines the safety of a standard hunting trigger with the accuracy of a competition trigger by adding a set trigger to the firing mechanism. The set trigger serves to reduce the pull force of the firing trigger. Double set triggers of the prior art use the set trigger to cock a hammer which may be released by a light pull on the firing trigger. The hammer strikes a catch to release the sear. Consequently, double set triggers of the prior art provide a light pull, but have a long lock time and high vibration.
Set triggers of the prior art are liable to accidental discharge if the bolt is withdrawn without firing the rifle. The bolt may then be closed with the firing mechanism set for the light pull, leaving the rifle susceptible to discharge resulting from impact.